NeuroToxicology

Depleted uranium (DU) is an environmental contaminant with a 30 g/L (ppb; parts per billion) EPA maximum contaminant level (MCL) for drinking water. The mining of uranium and use of DU in modern weapons underly human exposure that disproportionally impacts military and tribal communities in the United States. Uranium's radiotoxic characteristics are understood, but its chemical hazards much less so. In zebrafish (Danio rerio) and human cell cultures we test the hypothesis that exposure to DU negatively impacts cellular function and development through disruption of mitochondrial metabolism. Using a novel shrapnel model with TEM/SEM+EDS, we showed uranium microparticles caused proximity-dependent mitochondrial disruption. In waterborne exposure paradigms, larval movement was reduced and hatching delayed as a result of reduced movement and not enzyme deficiencies in response to 18 ppb DU, below the MCL. Increased DNA damage accumulation was detected in exposed larva and cells. DNA-damage quantitative PCR of DU-exposed larvae showed increased damage in the ahr1 locus (nuclear gene) and decreased mitochondrial DNA (mtDNA) copy number, but mtDNA damage levels varied across experiments. Mitochondrial function was assessed using a resazurin-based assay in the presence and absence of antioxidants and showed diminished cytoplasmic reductive capacity. DU exposure alone did not enrich antioxidant gene expression, contrasting with arsenic exposure, a known ROS-inducer and Nrf2-activator. Sulforaphane (SFN), a potent Nrf2-activator, did not blunt the effects of DU exposure, despite activation of antioxidant response element (ARE) genes (gstp and gss), but did blunt the effects of arsenic exposure. The most enriched transcript in DU-exposed larvae coded for slingshot protein phosphatase (ssh), further exploration revealed ssh1b as the zebrafish-specific ortholog activated in response to DU, and inhibition using an identified SSH1 inhibitor, Sennoside A, partially rescued the metabolic and hatching defects observed. Our data points to a cytotoxic mechanism in which DU disrupts mitochondrial function through ssh1b enrichment that impairs normal mitophagy, leading to decreased cellular reductive potential independent of either ROS production or ARE-activation. Our results suggest that health impacts from DU exposure may be directly linked to impaired mitochondrial functions.

High concentrations of steroidal hormone compounds are a growing source of concern for environmental pollution in aquatic ecosystems. In this study, we examine the effects of two estrogenic compounds (estriol and 17-ethinylestradiol) on fitness traits in the aquatic microcrustacean, Daphnia magna, a key bioindicator species for toxicology studies. The impacts were compared of two forms representing a natural and synthetic estrogenic compound. Growth and reproduction traits were assayed by exposing Daphnia to each estrogen type at four concentrations reflecting potential environmental exposure conditions up to acute toxicity levels (ranging from 0.1 - 50 {micro}g/L). Assaying the effects at a variety of concentrations is important given that it is known that hormone exposures can often result in non-monotonic responses. Both forms of estrogen impact a subset of the traits assessed, in some cases leading to beneficial changes and others causing harm. Estriol, the naturally-occurring estrogen, and EE2, the synthetic version, at high doses shift fitness traits in opposite directions such as adult growth rate as do at low doses for fecundity. In conclusion, our results support the need to assay a wide array of traits using multiple forms of steroidal hormones at a range of doses in order to assess non-monotonic patterns and their impact on an organismal fitness. In particular, assays that extend beyond the conventional measurements of lethality during acute exposure windows will be essential for understanding the impact of increased levels of hormone pollution on aquatic organisms and ecosystem health.

Alternaria mycotoxins represent an emerging concern due to their frequent occurrence in food and feed. However, available toxicological data remain limited. Under the current EU regulatory framework, and in line with the EFSA/ECHA/JRC guidance for the identification of endocrine disruptors (EDs), assessment of endocrine activity relies on standardized assays performed according to OECD Test Guidelines (TGs) for the estrogen-, androgen- and steroidogenesis- (EAS) modalities. Within the framework of the European Partnership for the Assessment of Risks from Chemicals (PARC), standardized in vitro methods of regulatory relevance were performed for six chemically characterized Alternaria toxins, aiming to address current regulatory gaps on EAS-mediated activity. Alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), altertoxin-I (ATX-I), tentoxin (TEN) and altenuene (ALT) were assessed over a broad concentration range, from 0.001 up to 60 M, depending on cytotoxicity and solubility profile of each compound. Our findings indicate estrogenic activity for AOH (PC50: 3.9 - 4.6 {micro}M) and AME (PC50: 5.2 - 8.5 {micro}M) in the estrogen receptor transactivation assay (OECD TG 455), as well as an anti-estrogenic activity for ATX-I (IC30: 0.27 - 0.37 {micro}M). Minimal positive responses were observed at high concentrations for AOH (from the dose of 3 {micro}M) and for AME (from the dose of 10 {micro}M) in the agonistic part of the androgen receptor transactivation assay (OECD TG 458), which may also reflect glucocorticoid receptor activation. No effects on estradiol or testosterone production were observed for any of the tested Alternaria compounds in the steroidogenesis assay (OECD TG 456).

Evidence of negative health and environmental effects of glyphosate-based herbicides (GBHs) has led to marketing of glyphosate-free formulations. A frequent glyphosate replacement is pelargonic acid, which is rapidly degraded, leading to claims of greater safety and less environmentally damaging than GBHs. However, toxicity of commercial pelargonic acid formulations containing several co-formulants have not been determined. Using Roundup NL, a representative pelargonic acid-based herbicide, we undertook tissue culture cell assays measuring viability, plasma membrane integrity, DNA damage, and activation of stress-response pathways. In human hepatoma HepG2 cells, Roundup NL was more cytotoxic than pelargonic acid, and more toxic than the GBH Roundup ProBio and glyphosate as shown by reduced viability underpinned by plasma membrane damage. Pelargonic acid and Roundup NL did not induce oxidative stress. However, comet assays revealed that pelargonic acid but not Roundup NL caused a modest but significant increase in DNA damage at sub-cytotoxic concentrations. The murine embryonic stem cell-based ToxTracker system confirmed Roundup NL as not directly genotoxic but triggered oxidative stress and protein damage (ER stress, impaired proteostasis) indicating cell and assay dependency of oxidative stress pathway activation. Our results suggest that exposure to pelargonic acid-based herbicides constitutes a health hazard and that co-formulants present in Roundup NL contribute substantially to its overall toxicity.

Alternaria toxins are naturally occurring food contaminants with limited and often inconsistent genotoxicity and mutagenicity data. Within the European Partnership for the Assessment of Risks from Chemicals (PARC), an OECD-aligned in vitro testing strategy was applied to fill existing data gaps and to characterize the genotoxic potential of major Alternaria toxins using high-purity test materials. Mutagenicity was assessed using bacterial reverse mutation test (OECD TG 471) and SOS/umu assay, while chromosomal damage was assessed using the in vitro micronucleus (MN) assay (OECD TG 487) in TK6 and HepG2 cells, complemented by fluorescence in situ hybridization (FISH) and {gamma}H2AX assay in HepaRG cells. Alternariol (AOH), alternariol monomethyl ether (AME), and altertoxin-I (ATX-I) showed clear mutagenicity in bacteria, whereas altenuene (ALT), tenuazonic acid (TeA), and tentoxin (TEN) were negative under the tested conditions. In mammalian cells, AOH, AME, and ATX-I induced MN formation in TK6 cells at concentrations [≥]5.5 {micro}M, [≥]2.5 {micro}M, and [≥]0.21 {micro}M, respectively, with FISH analysis supporting a clastogenic mode of action. In HepG2 cells, all tested toxins induced chromosomal damage, with effect threshold ranging from [≥]6.25 {micro}M (AOH) to [≥]50 {micro}M (TeA). {gamma}H2AX induction confirmed DNA damage for AOH and ATX-I, and at higher concentrations for TeA (1000 {micro}M). Overall, the data indicate clear in vitro genotoxic potential for AOH, AME, and ATX-I and provide evidence of chromosomal damage for ALT, TEN, and TeA, thereby reducing critical data gaps for hazard assessment.

Nanoplastics (NPs) are emerging environmental contaminants able to cross biological barriers, disrupt cellular and organelle homeostasis, and alter the brain microenvironment. This study investigated whether NPs affect microglia to neuron communication, a key mechanism underlying neuronal resilience, via the nuclear factor erythroid 2 like 2 (NFE2L2) pathway. Using an in vitro model, we evaluated the effects of polystyrene nanoplastics on microglial metabolic fitness and microglia-mediated neuronal stress responses. Increasing NP concentrations induced a dose dependent biphasic effect. Low to intermediate concentrations increased intracellular adenosine triphosphate (ATP) levels in microglia and enhanced microglia-mediated activation of neuronal NFE2L2. In contrast, high NP concentration impaired microglial metabolism, reduced ATP availability, and decreased microglia to neuron communication. These findings indicate that NPs alter microglial energetic status and modulate neuroprotective signalling, potentially contributing to impaired neuron to microglia interactions and increased susceptibility to neurotoxicity.

Tenuazonic acid (TeA) is an emerging Alternaria mycotoxin frequently detected in food and feed commodities, raising concerns about its toxicological relevance. Chronic oral exposure to TeA has been reported to induce dysplastic alterations in the esophageal mucosa of mice, while human biomonitoring data indicate an association between TeA exposure and esophageal cancer, although a causal relationship has not yet been established. At a mechanistic level, the effects of TeA in esophageal cells remain poorly characterized. Therefore, this study investigated the impact of TeA on cytotoxicity, oxidative stress, DNA damage, mitochondrial homeostasis, cell-cycle distribution and transcriptomic stress responses in human esophageal KYSE-510 cells. TeA induced a concentration-dependent reduction in metabolic activity and total protein content after 24 h exposure to 0.1-100 M. Significant cytotoxicity was measured starting from 20 M. At sub-cytotoxic concentrations, TeA triggered rapid ROS formation within 5-30 min exposure and induced formamidopyrimidine-DNA glycosylase (FPG) sensitive DNA damage after 1 h exposure (5-7.5 M), indicating oxidative DNA lesions. In addition, TeA altered mitochondrial morphology after 4 h exposure at 7.5 M, manifested by shrinkage of the mitochondrial network area and perinuclear redistribution, while mitochondrial respiration showed only a non-significant tendency towards reduced respiratory capacity. RNA sequencing after 6 h exposure to 10 M TeA revealed oxidative stress-associated transcriptional changes, impaired antioxidant and stress-adaptive responses, and p53-associated stress signaling. Furthermore, TeA induced significant G2/M phase accumulation after 24 h exposure to 1-10 M.

Fetal health is heavily dictated by the maternal environment. Inhaling airborne pollutants, like particulate matter, is associated with pregnancy complications and fetal developmental pathologies, including fetal growth restriction (FGR). Because fetal growth is dependent on the placental transfer of nutrients from the maternal circulation, particularly glucose, investigating glucose transport capacity is critical to understanding the development of FGR associated with gestational inhalation of particulate matter. Pregnant Sprague Dawley rats were exposed to titanium dioxide nanoparticles (9.8{+/-}1.0 mg/m3) as a proxy for ultrafine particulate matter, from gestational day (GD) 5 to GD 19 via whole-body inhalation. Glucose transporters (GLUTs) 1, 3 and 4 were evaluated in term placentas on GD 20 and ex vivo placental perfusion was conducted as a functional assessment of glucose transport. Exposure resulted in a reduction in Glut3 mRNA and GLUT1 protein. However, exposed placentas exhibited an adaptation, characterized by increased GLUT4 expression and membrane localization of both GLUT1 and GLUT4. Placental perfusion confirmed these molecular changes, revealing increased glucose flux in exposed placentas compared to control (AUC 95% CI: 77.4 to 127.5 vs 39.1 to 73.6, respectively). Contrary to our hypothesis, exposure to these nanoparticles enhanced glucose transport across the placenta. Here we have demonstrated that inhaling airborne pollutants during pregnancy modulates placental function and nutrient transport mechanisms, which can have direct effects on fetal development. Furthermore, we provide evidence for targeted interventions, aimed at mitigating fetal developmental pathologies. HighlightsO_LIGestational inhalation of nanoparticles decreases GLUT1 expression in the placenta. C_LIO_LIThe placenta adapts to gestational nanoparticle inhalation by enhancing GLUT4 expression and GLUT1 and GLUT4 membrane localization. C_LIO_LIEx vivo placental perfusion demonstrated increased glucose flux across to the placenta to the fetus following gestational inhalation of nanoparticles. C_LI

Tenuazonic acid (TeA) is one of the most frequently detected Alternaria mycotoxins in contaminated food. Despite its frequent occurrence, its immunomodulatory effects remain insufficiently characterized. Therefore, the present study investigated the impact of TeA on inflammatory signaling and cytokine regulation in monocytes and intestinal epithelial cell (IEC) models. NF-{kappa}B activity was assessed using a reporter gene assay in THP1-Lucia monocytes, while cytokine mRNA expression and protein secretion were quantified in Caco-2 and HCEC-1CT cells by qRT-PCR and ELISA, respectively. In THP-1 monocytes, TeA significantly suppressed lipopolysaccharide (LPS)-induced NF-{kappa}B activation in a concentration-dependent manner starting at 25 M, while cytotoxicity occurred only at concentrations [≥]100 M. In HCEC-1CT and differentiated Caco-2 cells, TeA increased IL-6, IL-8, and TNF- mRNA levels at non-cytotoxic concentrations ([≥]10 M). In Caco-2 cells, these transcriptional changes were accompanied by increased cytokine secretion, whereas HCEC-1CT cells showed only partial effects on the protein level after short-term exposure. Following prolonged incubation, TNF- secretion was increased and IL-6 and IL-8 secretion were slightly reduced. IL-10 remained unaffected under all conditions. Overall, TeA exerted cell type-dependent immunomodulatory effects characterized by immunoinhibitory activity in monocytes and pro-inflammatory responses in IECs, highlighting the complex immunotoxic potential of this Alternaria mycotoxin.

Introduction: Pediatric nicotine exposures remain an important and preventable public health issue, particularly with the rapid expansion of electronic nicotine delivery systems. This study compared demographic characteristics, exposure circumstances, and clinical outcomes between pediatric cases involving nicotine devices and bottled liquids reported to U.S. poison centers. Method: This retrospective cohort study analyzed National Poison Data System cases from 2011-2022 involving children aged less than 6 years exposed to nicotine devices or bottled liquids. Analyses were limited to cases with definitive medical outcomes. The primary outcome was defined as a moderate or major clinical effect or death. Odds ratios with 95% confidence intervals were calculated, with a secondary analysis restricted to route-concordant exposures. Results: The final cohort included 15,497 cases: 10,168 device exposures and 5,329 liquid exposures. Demographic characteristics were similar between groups. Device exposures more frequently involved inhalation, while ingestion predominated overall. Clinical effects were typically mild and transient, with vomiting and coughing most commonly reported. The primary outcome occurred in 1.9% of device cases and 2.0% of liquid cases (OR = 1.05; 95% CI 0.82-1.34). A secondary analysis restricted to inhalation-only device exposures and ingestion-only liquid exposures similarly found no significant difference in clinically important outcomes (OR = 1.38; 95% CI 0.92-2.12). Two deaths occurred, one in each group. Conclusion: These findings suggest that, despite differences in formulation and route of exposure, nicotine devices and bottled liquids produce broadly similar clinical toxicity profiles in young children. Prevention strategies should address all household nicotine products rather than focusing on specific delivery systems.

Copper (Cu) is an essential metal involved in neurobiological processes including energy metabolism and neurotransmission, yet dysregulated Cu levels may adversely affect brain health and olfactory performance. Although olfactory dysfunction has primarily been studied in older adults and neurodegenerative disease, adolescence is a critical period of brain maturation during which the olfactory system may be particularly vulnerable. This cross-sectional study examined associations between Cu exposure, olfactory bulb (OB) volume, and olfactory performance in 200 adolescents and young adults (64% female; ages 13 - 25) from the Public Health Impact of Metals Exposure cohort. Cu concentrations in blood, urine, hair, and saliva were measured using inductively coupled plasma mass spectrometry. T2-weighted magnetic resonance imaging scans estimated left, right, and total OB volumes using a three-stage deep learning pipeline. Olfactory performance was assessed using the Sniffin Sticks test. Weighted quantile sum regression evaluated associations between a Cu mixture index and OB outcomes, while standard linear regression models assessed individual Cu biomarkers. Models were adjusted for age and sex. A higher Cu index was associated with reduced left (Beta= -0.72, 95% CI [-1.42, -0.02]), right (Beta = -0.79, 95% CI [-1.43, -0.15]), and total OB volume (Beta= -1.55, 95% CI [-2.85, -0.25]), as well as lower odor threshold scores (Beta = -0.23, 95% CI [-0.42, -0.03]). Individual biomarkers were not independently associated with outcomes. These findings suggest that Cu exposure may adversely affect olfactory neurodevelopment during adolescence and highlight the importance of studying environmental exposures relevant to long-term neurological health.

Microplastics are pervasive environmental pollutants increasingly implicated in adverse human health effects, with emerging evidence linking MPLs exposure to elevated cardiovascular risk, including atherosclerosis. However, their specific mechanisms of action remain unknown. Human aortic endothelial cells (HAECs), located in the innermost layer of blood vessels, play a crucial role in maintaining vascular homeostasis and the development of atherosclerosis. This study demonstrates that polystyrene microplastics (80 nm MPLs) can enter HAECs through multiple pathways, including macropinocytosis, clathrin-mediated endocytosis, and caveolin-mediated endocytosis, and co-localize with mitochondria and lysosomes. MPLs exposure resulted in coordinated transcriptional, epitranscriptomic, and metabolomic reprogramming in HAECs, characterized by disruption of mitochondrial genes and an inflammatory response with activation of TNF-a; and NF-kB signaling. Integrative analysis revealed remodeling of the epitranscriptomic profile, demonstrated by an increase in 1-methyladenosine (m1A) modification along with reciprocal regulation (TRMT61A upregulation and ALKBH3 suppression) of its transcriptomic machinery, alongside other enzymes associated with 3-methylcytidine (m3C), pseudouridine (Y), 5-methylcytidine (m5C), and 7-methylguanosine (m7G) pathways. By comparing transcriptomic data from MPLs-treated HAECs with those of human atherosclerotic plaques, several common dysregulated pathways were identified, particularly those related to vascular physiological regulation and cell signaling. Metabolomic profiling further revealed significant remodeling of lipid metabolic networks associated with oxidative stress and inflammatory signaling. In summary, this study reveals that HAECs can internalize MPLs, leading to multiple disturbances in the transcriptome, epigenome, and metabolic networks, suggesting that MPLs exposure may pose a potential hazard to human cardiovascular health.

Octodon degus are long-lived, diurnal, and highly social rodents increasingly used in studies of aging and neurodegeneration. However, behavioral profiles of aged laboratory-housed degus remain incompletely characterized, limiting the interpretation of aging-associated functional and molecular phenotypes in this species. Here, we evaluated age-associated changes in locomotor activity, open-field exploration, social novelty behavior, and manually scored ethological responses in young and old degus maintained under long-term laboratory housing conditions. Automated behavioral tracking was performed during open-field testing and three-chamber social behavior testing. During open-field testing, old degus showed increased locomotor activity compared with young animals, including greater total distance moved, higher mean velocity, increased moving frequency, and longer cumulative movement duration. Old degus also showed increased center-zone duration and reduced thigmotaxis score. Manual ethological scoring revealed increased rearing and fecal boli in old animals during open-field exposure. In the three-chamber social behavior assay, young degus showed higher investigation frequency toward the novel intruder than toward the familiar cagemate, whereas old degus showed a lower social novelty discrimination index compared with young animals. Sex-stratified analyses did not identify significant male-female differences within young or old groups for the major open-field or social novelty metrics examined. Together, these findings indicate that aging in laboratory-housed degus is associated with a mixed behavioral profile involving increased stress-related ethological responses and reduced social novelty preference reminiscent of dementia-like behavioral changes observed in Alzheimers disease. This behavioral framework provides a practical reference for future studies examining behavioral heterogeneity and molecular correlates of brain aging in degus. Lay SummaryOctodon degus are long-lived, highly social rodents that are increasingly used to study aging and age-related neurodegenerative disorders. However, interpreting behavioral changes in aged degus requires a clear understanding of how aging affects activity, exploration, social behavior, and stress-related responses under laboratory housing conditions. In this study, we compared young and old degus using open-field testing, three-chamber social behavior testing, automated video tracking, and manual scoring of selected behaviors. Aged degus did not show a simple reduction in behavioral activity. Instead, they showed increased movement during behavioral testing, increased rearing behavior, greater exploration of the center of the open-field arena, and increased fecal output during open-field exposure. These findings suggest that aged degus show increased exploratory activity together with altered stress-related responses in a novel environment. Aged degus also showed reduced preference for investigating a novel social partner, consistent with a dementia-like cognitive impairment. Together, these results define a behavioral profile of aged laboratory-housed degus and provide a practical reference for future studies using this species to investigate aging, social behavior, and neurodegeneration-related phenotypes.

Bisphenol S (BPS), a widely used substitute for bisphenol A, is increasingly detected in aquatic environments; however, its neurodevelopmental effects remain insufficiently understood. This study investigated whether developmental exposure to an environmentally relevant concentration of BPS disrupts social behaviour and underlying neurobiological pathways in zebrafish (Danio rerio). At 21 days post-fertilization, BPS-exposed larvae exhibited a significant reduction in social preference, indicating impaired conspecific interactions. Neurochemical analysis revealed a marked increase in serotonin (5-HT) levels, whereas lipid peroxidation (MDA) remained unchanged, suggesting the absence of overt oxidative damage. Gene expression profiling demonstrated a dysregulated antioxidant response, suppression of apoptotic signaling, and pronounced upregulation of serotonergic receptors and transporters. To resolve system-level mechanisms, protein-protein interaction (PPI) network analysis identified BDNF and CREB1 as dominant regulatory hubs, with the serotonergic synapse pathway as the most significantly enriched term. Molecular docking further demonstrated direct binding of BPS to multiple serotonergic targets, including HTR1A and TPH2, supporting receptor-level interference. Expanded network and pathway analyses revealed coordinated enrichment of monoamine GPCR, oxidative stress, and inflammatory pathways. These findings demonstrate that BPS induces serotonergic dysregulation and network-level reprogramming rather than significant oxidative damage, leading to behavioural impairment. This study provides a multi-scale mechanistic framework linking molecular perturbations to neurobehavioural outcomes, identifying serotonergic signaling and BDNF-CREB1 pathways as central targets of BPS neurotoxicity.

Companion animal brain banking has been recognized as a valuable approach for translational aging and dementia research. However, realizing the full value of canine brain banks depends on optimizing the methods that are used to collect and preserve the tissue. Whole brain perfusion fixation is one promising approach, but it is not yet well described in dogs. Here we describe the development of methods for a canine brain bank (currently n = 55), including whole brain perfusion fixation via aortic cannulation and brain extraction. We assessed perfusion quality using gross examination, post-perfusion CT, and histological clearance of blood vessels. We found that body weight and average flow rate per body weight were each significantly correlated with perfusion quality in our cohort. To illustrate the kind of analysis the bank could facilitate, we next performed a preliminary study of brain aging, one of our primary planned research applications. Using a pixel classifier applied to whole slide images, we quantified lipofuscin burden, and in this preliminary cohort found that it increased strongly with age in both the thalamus and hippocampus. In the hippocampus, lipofuscin burden was also elevated in dogs with owner-reported cognitive dysfunction, although the current cohort is too small to determine to what extent this association is independent of age. Preliminary electron microscopy studies also confirmed that perfusion fixed tissue from the bank is amenable to ultrastructural analysis. This work describes one approach for canine brain perfusion fixation and introduces a brain tissue resource that may help support future neuroscience research.

Wood is commonly used in the building sector, emitting volatile organic compounds (VOCs) contributing to indoor air quality. These VOC profiles can have a pleasant smell and positive effects e.g., induce relaxation. Contrarily, VOCs can have adverse health effects in higher concentrations. Therefore, some VOCs are regulated by guide values (GV). Potentially positive and negative effects of pinewood emissions, ranging from 0.2 mg/m3 (German GV I for bicyclic terpenes) to 2.0 mg/m3 (GV II) were investigated in an experimental 2 h exposure study using a within-subject design. Thirty-two healthy participants rated the perception, pleasantness, symptoms of irritation, and indicators of well-being. During a demanding working memory task (n-back) and a resting period, heart rate (HR) and HR variability (HRV) changes were measured. Before and after each session physiological markers of sensory irritation were assessed. Ratings indicated that the exposure to GV I and GV II were not perceived as more intense or pleasant. Mostly concentration-independent effects were revealed, indicating that inter-individual factors influenced the ratings rather than the VOCs. The pinewood odors during the n-back task did not cause distraction nor did it facilitate performance as previously suggested. HR/V changes indicated that pinewood odors during and after the n-back tasks did not induce relaxation. Only symptoms of nasal irritation showed some weak concentration-dependency, not supported by physiological markers or comparable ratings of sensory irritation. In conclusion, the fact that no distinct odor is detected suggests that interfering factors potentially prevent the regulation of odors at relevant indoor air concentrations.

Traumatic brain injury (TBI) is a characteristic feature of neurodegenerative diseases such as Alzheimers disease and chronic traumatic encephalopathy. Small animal models have been used to establish clinically relevant biomarkers of neuropathology, however, they show significant anatomical differences from humans and are affected by artificial experimental manipulations, making them often unsuitable for longitudinal study of repetitive mild TBI. Building on a previous study of neuropathology in headbutting bovids in the wild, this pilot study investigated whether freely headbutting domestic goats, which naturally engage in low-intensity, high-frequency head impacts, accumulate measurable biomarkers of neurodegeneration in cerebrospinal fluid (CSF) and brain tissue. Over a six-month period, three male goats (Capra hircus) were allowed to freely headbutt under continuous video surveillance. Monthly CSF samples were collected, and concentrations of key neurodegeneration biomarkers were measured via multiplex immunoassays, including amyloid {beta} ; peptides (A {beta} 40, A {beta} 42), total and phosphorylated tau (tTau and pTau), glial fibrillary acidic protein (GFAP), S100 calcium-binding protein B (S100B), and neurofilament M (NF-M). Postmortem immunohistochemistry was conducted on prefrontal cortical tissues using antibodies targeting pTau, GFAP, and S100B. Head impact kinematics were quantified using horn-mounted accelerometer and inclinometer sensors that recorded linear acceleration, rotational velocity, and head orientation during naturally occurring headbutting events. Several notable trends were observed. Phosphorylated tau as well as reactive astrocytes were detected in the brain tissue, mirrored by elevated GFAP detected in the CSF. PET TSPO was unsuccessful, however, FDG PET revealed frontal-dominant activity in all goats, and one with asymmetrical activation. Overall, the goats sustained 5,000-7,000 head impacts each over six months, with forces up to 388 N and peak acceleration up to 16.5 g. This multi-modal observational study is the first to characterize neurodegeneration biomarkers and kinematics in headbutting goats. Even at one year old, the combination of pTau and gliosis in both the brain tissue and CSF indicates that the goat s repetitive head impacts begin to show neurodegenerative consequences early in life. Likely, the severity of these consequences increases with headbutts and age, eventually resulting in chronic neurodegeneration. This system shows promise as a large-animal model for the longitudinal study of the onset and progression of neurodegenerative disease.

Traumatic brain injury (TBI) has long-term consequences that include chronic traumatic encephalopathy (CTE) and an elevated risk for Alzheimer Disease (AD). These dementias ultimately manifest as tauopathies but may begin with acute neuronal dysfunction including post-traumatic seizures. Provocative evidence suggests that these prodromal seizures are a viable target to mitigate the later onset of dementias, and anti-epileptic drugs (AED) that increase the threshold of action potentials have indeed been shown to mitigate later tauopathies[1, 2]. Here, we test whether AEDs and other compounds that modulate synaptic transmission, applied immediately after TBI, can also act as prophylactics that block subsequent CTE-like tau aggregation and neurodegeneration in a larval zebrafish model. Levetiracetam (LEV) is an AED that modulates synaptic vesicle release. Application of LEV immediately following TBI abrogated TBI-induced tau tau aggregation (IC50 = 3.168 x10-3 mM) and cell death in the larval zebrafish TBI model. We next considered a polypharmacy approach involving mGluR2, because mGluR2 positively allosteric modulators (PAMs) such as JNJ-42153605 have previously been able to improve LEVs action in reducing some recalcitrant forms of seizure in a mouse model. We found that JNJ-42153605 was itself effective at blocking TBI-induced tau aggregation (IC50 = 8.691 x10-5 mM). Moreover, a subeffective dose of JNJ-42153605 (10-5 mM) was able to substantially improve the efficacy of LEV (~16-fold) in its prophylactic actions. Thus, LEV and JNJ-42153605 applied briefly after TBI offer a potent polypharmacy approach, at least in our preclinical animal model, to tackle the later tau aggregation and neurodegeneration that follows from TBI neurotrauma. These results warrant further investigation, including testing into mammalian TBI models (with longer disease course).

Alternaria fungi produce various structurally diverse mycotoxins, several of which exhibit immunomodulatory properties. Among these, alternariol monomethyl ether (AME), alternariol (AOH), alterperylenol (ALTP), altertoxin I (ATX-I), and altersetin (AST) have been reported to suppress lipopolysaccharide (LPS)-induced inflammatory responses. However, the precise molecular mechanisms underlying these effects remain unclear. The present study aimed to elucidate how these selected Alternaria mycotoxins (0.1-50 M) target the NF-{kappa}B signaling pathway in THP-1 monocytes. Key components of the NF-{kappa}B cascade were analyzed by immunofluorescence microscopy, Western blotting and qRT-PCR. Nuclear translocation of NF-{kappa}B p65 and its phosphorylated form (p- NF-{kappa}B p65) was assessed by Western blot, while cytokine responses were determined at transcript (qRT-PCR) and protein (ELISA) levels. Moreover, in silico docking analyses were performed to investigate potential interactions of the toxins with IKK{beta}, and receptor-mediated crosstalk was studied using the glucocorticoid receptor (GR) antagonist RU486. Co-treatment with RU486 attenuated the immunosuppressive effects of 1 and 5 M AOH, indicating partial involvement of GR-dependent mechanisms. AME, AOH, ALTP, ATX-I, and AST increased total I{kappa}B levels while reducing its phosphorylated form. Additionally, AST and ALTP decreased the protein levels of Toll-like receptor 4 (TLR4), the I{kappa}B kinase (IKK) complex, NF-{kappa}B p65, and p- NF-{kappa}B p65. While AOH (5 M) and AST (25 M) reduced nuclear translocation of p65 and p-p65, ALTP (2 M) enhanced nuclear localization despite decreasing cytokine expression. Together, these findings suggest toxin-specific interference at multiple regulatory levels of NF-{kappa}B signaling and provide novel mechanistic insight into the immunomodulatory effects of Alternaria mycotoxins.

Hereditary spastic paraplegia type 7 (SPG7) is a neurodegenerative disorder characterized by progressive motor impairment and cerebellar dysfunction. Mutations in the SPG7 gene, encoding the mitochondrial metalloprotease paraplegin, disrupt mitochondrial homeostasis and lead to neuronal vulnerability and deficits in motor coordination. Recent studies have identified defective flickering of the mitochondrial permeability transition pore (mPTP) in SPG7 models, suggesting that altered pore dynamics may represent a functional biomarker of mitochondrial dysfunction. Here, we investigated whether pharmacological modulation of mPTP activity could improve mitochondrial function and motor performance in SPG7 models. Mitochondrial flickering was assessed in vitro, while motor behavior was evaluated in vivo following chronic treatment with berberine, a natural isoquinoline alkaloid known to modulate mitochondrial bioenergetics. Spg7-/- mice and age-matched Spg7+/ littermate controls received daily oral berberine administration for several weeks, and motor coordination was assessed using the accelerating rotarod test. Untreated Spg7-/- mice exhibited reduced rotarod performance compared with controls, indicating impaired motor coordination. Berberine treatment significantly improved motor performance in pre-symptomatic mutant mice. These findings indicate that pharmacological modulation of mitochondrial permeability transition pore dynamics can ameliorate motor dysfunction associated with SPG7 deficiency and highlight mPTP flickering as a functional readout of mitochondrial health.